Heat rash in the nappy area: what parents should know

A nappy can hold warmth and moisture against delicate skin, while urine, stool, and rubbing add irritation. Heat rash may appear as fine red or clear bumps in covered areas. Nappy dermatitis can look similar, and yeast-related irritation may be bright red with spots beyond the main patch. The appearance and skin folds help a clinician tell these apart. Read more about [Heat Rash](/conditions/heat-rash/), [Skin Bumps](/symptoms/skin-bumps/), and [Skin Redness](/symptoms/skin-redness/).

Change wet or soiled nappies promptly. Rinse with lukewarm water or use a fragrance-free cleanser, then pat every fold dry. Give short nappy-free periods in a warm safe room and avoid tight fastening. Do not scrub, use fragranced wipes, or apply talc. A barrier product may be suitable for some forms of irritation, but ask a clinician before using a thick product over bumps that may be heat rash. [Emollient Therapy](/treatments/medical-dermatology/emollient-therapy/) and [Topical Corticosteroids](/treatments/medical-dermatology/topical-corticosteroids/) should be used only as directed for the diagnosed problem.

Contact a clinician if the rash has open skin, blisters, pus, crusting, bleeding, marked tenderness, or a strong smell, or if it is not improving after careful drying and cooling. Seek urgent help if the baby is feverish, unusually sleepy, feeding poorly, or producing fewer wet nappies. Rapidly spreading redness or swelling also needs prompt assessment because infection can worsen beneath a nappy.

Ask whether the pattern fits heat rash, irritant nappy dermatitis, or yeast; which wipes and barrier products to use; and when the baby can return to the usual nappy routine. Mention recent antibiotics, diarrhoea, fever, and any product change.